(a) Technical Field
The present disclosure relates, in general, to a receptacle filter for charging hydrogen. In particular embodiment, it relates to a receptacle filter for charging hydrogen which can reliably remove impurities from hydrogen gas when charging hydrogen into a tank by virtue of the structure in which a filtering unit manufactured by sintering metal powder is suitably installed in a receptacle for charging hydrogen.
(b) Background Art
Generally, fuel cell vehicles using hydrogen as their fuel include one or more hydrogen tanks under a pressure of 350 bar or 700 bar.
In a system for charging hydrogen into such a hydrogen tank, the pressure in the hydrogen tank is suitably measured by a pressure sensor which is preferably provided in a dispenser of a hydrogen charging station or in the hydrogen tank, and when the measured pressure reaches the desired pressure, the charging is suitably stopped.
Preferably, when charging hydrogen into the hydrogen tank, a receptacle for charging high-pressure hydrogen is typically used, functioning as a kind of connector. In further preferred embodiments, a filter is installed in the receptacle to remove impurities from hydrogen gas when it is being charged.
According to certain preferred embodiments, in the system for charging high-pressure hydrogen into the hydrogen tank and storing it therein, two filters are suitably arranged in a direction in which hydrogen gas is suitably charged into the hydrogen tank. Preferably, one of the filters is suitably installed in the receptacle at an upstream side with respect to the charging direction of hydrogen and suitably functions to remove impurities from hydrogen gas drawn from the hydrogen station. In further embodiments, the other one of the filters is a regulator filter which is suitably disposed behind the filter installed in the receptacle and serves to remove impurities to prevent the impurities from entering a fuel cell stack.
Preferably, the filter installed in the receptacle has a fine porous structure having pores ranging from 40 μm to 50 μm in diameter. According to further embodiments, this filter first removes impurities from hydrogen gas when charging it into the tank. Preferably, the regulator filter is disposed in the front of a regulator and has a mesh structure. When hydrogen gas is reduced in pressure from 350 bar or 700 bar to 10 bar by the regulator, the regulator filters hydrogen gas to prevent impurities from entering the fuel cell stack.
Hereinafter, the construction of a conventional receptacle filter will be explained according to certain preferred embodiments of the present invention.
Preferably, as a representative example of the conventional technique, for example as shown in FIG. 4, a filter 100 for fluid pipes was proposed in Korean Patent Registration No. 10-790199, incorporated by reference in its entirety herein. Preferably, the filter 100 includes a filter body 104 which has fluid passing holes 102 therein, and a spring wire 106 which is suitably wound around the surface of the filter body 104 and preferably covers the fluid passing holes 102 to function as a filtering member. However, the conventional receptacle filter has a relatively large number of components and a complex structure, wherein the complex structure is such that the fluid passing holes must be suitably formed through the filter body 104 and the spring wire must be suitably wound around the surface of the filter body 104 in several turns or several tens of turns. Further, the filtering of hydrogen gas is suitably realized by fine gaps between the wound portions of the spring wire, but the fine gaps are relatively large so that hydrogen gas too easily passes through the fine gaps, thus suitably deteriorating the filtering performance.
Another example of the conventional technique was proposed a filter in which a filter body preferably made of SUS has as part of its own construction a plurality of fine pores. However according to this construction, impurities cannot be satisfactorily removed from hydrogen gas just by the fine pores.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.